How to Prove This Complex Inequality Involving Absolute Values?

AI Thread Summary
The discussion revolves around proving the inequality |(1/2)(a+b)|^p ≤ (1/2)(|a|^p + |b|^p) for complex numbers a and b. A suggested approach involves manipulating the inequality by introducing terms that account for the complexity of the expression. However, concerns are raised about the validity of subtracting terms like pab, particularly when p is not equal to 2, which may lead to inaccuracies in the proof. The conversation highlights the challenges in handling absolute values and powers in inequalities. Ultimately, the need for a rigorous proof method remains a central focus.
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Need help with a complex inequality??

hey!
i been trying to do this inequality for a 2 hrs now and can't seem to prove it
|\frac{1}{2}(a+b)|^p \leq \frac{1}{2}(|a|^p+|b|^p) where a,b are complex numbers
Can anyone suggest a way??
thanks
 
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Try this:

|\frac{1}{2}(a+b)|^{p}\leq(\sqrt[p]{\frac{1}{2}}|(a+b)|)^{p}-pab

Yes, I know, the last term is only pab if p=2, but you will always be subtracting somthing at the end, no matter the value of p. I think this kinda works...
 
so you saying that |\frac{1}{2}(a+b)|^{p}\leq(\sqrt[p]{\frac{1}{2}}|(a+b)|)^{p}-pab \leq \frac{1}{2}(|a|^p+|b|^p)
 
for p = 1
|\frac{1}{2}(a+b)|\leq(\frac{1}{2}|(a+b)|)-ab
isnt this false because you subtracting a ab on the RHS?
 
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